I have an FTP server that needs a certificate to perform FTPS connections. I set up certbot a while ago to get certificates for the server using the Standalone method, since there wasn’t a web server on this machine I needed to worry about. Port 80 is open to the machine specifically for certificate renewals. However, a few months ago, when trying to renew the certificate, it would sit on the “Waiting for verification…” stage for some time, then throw a timeout exception.
Can someone help me track down what might be going wrong with this renewal process? FTP connections to the server are working fine, but apparently HTTP requests to the server aren’t going through during the renewal process. I can port scan the IP while the renewal is happening and it detects that port 80 is open on the machine, but requests just end up timing out.
My domain is: ftp.altalang.com
I ran this command: sudo certbot renew --force-renewal
It produced this output:
Saving debug log to /var/log/letsencrypt/letsencrypt.log
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Processing /etc/letsencrypt/renewal/ftp.altalang.com.conf
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Plugins selected: Authenticator standalone, Installer None
Renewing an existing certificate
Performing the following challenges:
http-01 challenge for ftp.altalang.com
Waiting for verification...
Cleaning up challenges
----------------------------------------
Exception happened during processing of request from ('::ffff:52.28.236.88', 26590, 0, 0)
Traceback (most recent call last):
File "/usr/lib/python3.6/socketserver.py", line 320, in _handle_request_noblock
self.process_request(request, client_address)
File "/usr/lib/python3.6/socketserver.py", line 351, in process_request
self.finish_request(request, client_address)
File "/usr/lib/python3.6/socketserver.py", line 364, in finish_request
self.RequestHandlerClass(request, client_address, self)
File "/usr/lib/python3/dist-packages/acme/standalone.py", line 206, in __init__
BaseHTTPServer.BaseHTTPRequestHandler.__init__(self, *args, **kwargs)
File "/usr/lib/python3.6/socketserver.py", line 724, in __init__
self.handle()
File "/usr/lib/python3/dist-packages/acme/standalone.py", line 215, in handle
BaseHTTPServer.BaseHTTPRequestHandler.handle(self)
File "/usr/lib/python3.6/http/server.py", line 418, in handle
self.handle_one_request()
File "/usr/lib/python3.6/http/server.py", line 386, in handle_one_request
self.raw_requestline = self.rfile.readline(65537)
File "/usr/lib/python3.6/socket.py", line 586, in readinto
return self._sock.recv_into(b)
ConnectionResetError: [Errno 104] Connection reset by peer
----------------------------------------
Attempting to renew cert (ftp.altalang.com) from /etc/letsencrypt/renewal/ftp.altalang.com.conf produced an unexpected error: Failed authorization procedure. ftp.altalang.com (http-01): urn:ietf:params:acme:error:connection :: The server could not connect to the client to verify the domain :: Fetching http://ftp.altalang.com/.well-known/acme-challenge/pws10BMqkHVInpoGJZOAdYufl7rudAMyl2SY3BBwxKA: Timeout after connect (your server may be slow or overloaded). Skipping.
All renewal attempts failed. The following certs could not be renewed:
/etc/letsencrypt/live/ftp.altalang.com/fullchain.pem (failure)
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All renewal attempts failed. The following certs could not be renewed:
/etc/letsencrypt/live/ftp.altalang.com/fullchain.pem (failure)
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Running post-hook command: /etc/letsencrypt/renewal-hooks/post/restart-proftpd.sh
1 renew failure(s), 0 parse failure(s)
IMPORTANT NOTES:
- The following errors were reported by the server:
Domain: ftp.altalang.com
Type: connection
Detail: Fetching
http://ftp.altalang.com/.well-known/acme-challenge/pws10BMqkHVInpoGJZOAdYufl7rudAMyl2SY3BBwxKA:
Timeout after connect (your server may be slow or overloaded)
To fix these errors, please make sure that your domain name was
entered correctly and the DNS A/AAAA record(s) for that domain
contain(s) the right IP address. Additionally, please check that
your computer has a publicly routable IP address and that no
firewalls are preventing the server from communicating with the
client. If you're using the webroot plugin, you should also verify
that you are serving files from the webroot path you provided.
My web server is (include version): None – this is just an FTP server (ProFTPD)
The operating system my web server runs on is (include version): Ubuntu 18.04 LTS
My hosting provider, if applicable, is: N/A (using our own hardware)
I can login to a root shell on my machine (yes or no, or I don’t know): Yes
I’m using a control panel to manage my site (no, or provide the name and version of the control panel): No
The version of my client is (e.g. output of certbot --version or certbot-auto --version if you’re using Certbot): 0.31.0